Method of preparing food products



Patented an 21, 19a:

siszzz Eran sures PATENT orlucs JAMES 3'. BARRY AND WILLIAM T. MURRAY,01? GLOUCESTER, MASSACHUSETTS, AS- SIGBIORS, BY MESNE ASSIGNMENTS,TCQEBIOSTED FOODS COMPANY, INC., DOVER, DELAWARE, A COBEORATION OFDELAWAB'E mrnon or reexamine noon necrosis in Drawing.

This invention relates to methods of preparing food products, andparticularly to the pre aration thereof for canning.

eretofore, considerable difiiculty has'been,

u experienced in canning of certain food prod nets of which fish perhapsheads the list, be

cause of the black spots or black coating which appears in the cans whenopened,

' either in the product, on the can, or both. Ihis dificulty hasoccurred because of the presence of hydrogen and sulphur or hydrogensulphide in the product after cannlng and of iron in the container. Freehydrogen,

and sulpiiur combine to form hydrogen sulphide attacks the iron of thecontainer forming iron sulphide (FeS) which is blacln- Heretoforeefforts have been directed to the prevention of this black deposit or ofthese black specks lay preventing the fish or other product coming incontact with the container. Some have used lacquered cans, others havelined the cans or wrapped the roduct as with parchment, and other have0th lacquered the cans as and lined them. Such means are, however,

merely temporary and unsatisfactory preyentatiyes and not uniailingcuresof the trouble.

Our invention has for its objects to elimi- 30 nate the formation ofsulphides, particularly iron sulphide, in the canned product; to sliminate'free sulphur from the product; to enable servative substances in te canned product;

to secure the elimination of the sulphur in the same process hy whichthe product is other- Wisereparedfor cannin to secure simplicity 0operation and fulfillment of the purposes and steps of the inventiomandto obtain other advantages and results as may be brought out in thefollowing description.

In can-yin out our invention, we prepare and this being acid in natureApplication filed January" 5, 1927. Serial E0. 159,238.:

the product for canning by cooking or heating the product at adequatetemperatures. By preference, this cooking or heating. is suflicient toloosen the fish flesh from the bones, to eliminate surplus moisture,orto accomplish other desirable results in the preparation of theproduct for canning. Preferably, also, thisheating or cooking of theproduct is performed in the presence of lead, as in a lead container. Asa result of use of lead in this heating of the food product, the freesulphur in. the product is eliminated and the black spots or coatingwill not appear in the cans in which the product is next sealed, even ifunlined or unlacquered cans aroused.

It appears that the reactions resulting from carrying out our processare substantially that by cooking or heating the product the sulphurtherein unites with oxygen of the air or within the vessel in which theprocess isbeing carried out, forming sulphur di-oXide (S0 Thatin turnwould appear to unite with hydrogen, forming the electrolytic compoundofsulphurous acid (H SOS) Likewise, the heat has caused the lead surfaceto become oxidized, forming lead oxide (PbO) which unites with thesulphurous ion forming lead sulphate (PbSOQ. Free sulphur is thuseliminated by this process, and canning of the product is thereafter completed in the usual way.

While we have indicated above that the process is carried out by'heatingin the pres-c ence of lead simultaneously with cooking or sterilizationof the product, it is obvious that these steps may be taken separately,and that the heating may be by boiling, steaming, or otherwise, and alsothat other detail changes and modifications may he made in carrying outof our process, both as to the steps performed or the order v ofperforming such steps, and we do not wish to be understood as limitingourselves to such detaiis except 1 as set forth in the following claimswhen construed in thelight of the prior art.

Having-thus described the inventionfwe claim 1. {The hereindescribedmethod of'prevent-- ing 'biackfldeposit ingcans of canned food looproducts, comprising heating the product in the presence of lead. p

- 2. Thehereindescribed process of preventing black deposit in cans ofcanned food 5 products, consisting in combining sulphur of the productwith lead. 4 i

3. The hereindescribed method of preventing black deposit in cans ofcanned food products consisting in forming lead sulphate with thesulphur contained in said product.

4 The hereindescribed method of re- I venting black deposit in cans ofcanned cod products, consisting in heating the food product in a leadcontainer.

5. The hereindescribed method of prevent.- ing black deposit in foodproducts after canning, consisting in boiling the product in thepresence of lead, and thereafter canning said boiled product.

6. The hereindescribed method of preventing black deposit in cans ofcanned food products, consisting in steaming the food product prior tocanning .Withthe food roduct in the presence offllead while eing 2steamed, and canning said product after said steaming.

- WILLIAM T. MURRAY.

J. J. BARRY"

